problem with polish letters

Hi ! I have a problem with polish letters like ś ć ó ę ą ń . Sometimes it shows, some other times instead there is a symbol �. How can I fix it ? All settings of the computer are factory once and I didn’t have that problem with any other programs. Thanks for the solution! Mike
p.s. example of message “Statystyka miesi�czna dla agent�w” should be “Statystyka miesięczna dla agentów”

Hello Maciej, is this an issue with your incoming messages? What version of eM Client are you currently using on your computer, can you please check the exact release number in Help > About? What mail service are you using with eM Client?

Are you having this issue with all incoming messages or just some of the received messages?

Can you make a screenshot of the issue?

Thank you,